A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5975-01-410-7647
NSN 5910-00-596-3179
NSN 5915-01-200-0753
NSN 5935-01-461-9099
NSN 6145-01-620-7134
NSN 5920-01-441-0362
NSN 6110-01-163-2953
NSN 5950-00-593-9329
NSN 5910-01-543-9105
NSN 5960-00-009-4381
NSN 5960-01-543-0235
NSN 6610-01-004-5856